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Do the New England Patriots have a first-quarter problem?
On Sunday against the Buffalo Bills, the Patriots trailed 21-0 at the end of the first quarter, but came back to win. That had happened only seven times in NFL history.
The Patriots were actually the first team to lose after leading 21-0 going into the second quarter. That was 37 years ago, when the Miami Dolphins climbed back to a 34-27 win.
New England's win on Sunday -- particularly by such a large margin -- helped mask a growing trend of falling behind early.
In the Patriots' eight home games, they led just once at the end of the first quarter. Overall, they've trailed in the first quarter in half of their games. In six of those, New England trailed at the end of the first quarter.
Yet, New England proved adept at coming back from early deficits. In those six games in which they trailed going into the second quarter, the Patriots went 5-1. To put that in perspective, the rest of the NFL was just 58-146.
Those five wins when trailing after the first quarter are the most in a single season in Patriots history. The last team with more wins when trailing after the first quarter? The 2009 Saints, who won six on their way to a Super Bowl title.
Yet, postseason history says the odds are against teams that fall behind early. The Patriots are just 2-8 all-time in the postseason when trailing at the end of the first quarter. Over the past 10 postseasons, the team that's winning after the first quarter is 57-24.
But is history a true indicator? As long as the Patriots continue to bounce back this season, should these early deficits be a concern? The answer may require a closer look at just how New England is falling behind.
At issue is not just a poor defense, but an offense that's slow out of the gates.
The Patriots were outscored 87-82 in the first quarter, a minus-5 margin that ranked 20th in the NFL. Those 87 points allowed were eighth most. But starting in the second quarter, the Patriots outscored opponents by 176 points.
That discrepancy was far more apparent as the season went on. Over the final seven weeks of the season, the Patriots were outscored by a combined 29 points in the first quarter. In the final three quarters, they outscored opponents by a combined 141 points.
Over the last six weeks, New England allowed 57 points in the first quarter, but won all six games. Only the Buccaneers (66) allowed more, and they went 0-6 in that span.
Defensively, the culprit is a familiar one in 2011. The Patriots allowed 1,209 passing yards in the first quarter. That's the most since the 1995 Atlanta Falcons gave up 1,236.
Meanwhile, the Patriots' rushing attack tended to start very slowly. They gained only 305 yards in the first half, third fewest in the NFL.
Despite these early deficits, the Patriots always clawed back into the game. The pass rush played a key role in this. When trailing, New England has 12 sacks on 117 opponent dropbacks. Compare that to 23 sacks on 432 opponent dropbacks when the Patriots are ahead.
Of course, the comebacks really come down to Tom Brady. Perhaps the most overlooked aspect of his fine season has been Brady's play when the Patriots are trailing.
When playing from behind, Brady connected on 14 touchdowns and just one interception, good for a 106.5 passer rating. Brady hasn't always been a great comeback quarterback. Just two years ago, he had four touchdowns and three interceptions when the Patriots trailed.
This season, he's turned to the tight ends when on the comeback trail. When behind, Brady is 53-for-81 with nine touchdowns when targeting Rob Gronkowski and Aaron Hernandez.
Impact of the Coin Flips
It's easy to place blame on the defense or chalk it up to slow starts. But there may be a far more simple explanation for the early deficits faced by New England. Could it be as basic as the flip of a coin?
The Patriots received the opening kickoff only once all season. That's tied with the Packers for the fewest this season, while the 49ers got it just twice. Interesting to note: Those teams finished with three of the four best records in the NFL.
In 15 of 16 games, the Patriots' opponent started out with the ball. That certainly goes a long way toward explaining those early deficits.
This isn't a matter of bad luck. The Patriots won seven coin flips this season, opting to defer in each case.
In 2008, the league instituted a rule providing the option to defer the decision to kick or receive until the second half. New England has deferred all but once since. Overall, the Patriots have deferred 28 straight winning coin flips, last opting to receive on Sept. 7, 2008. In that span, only the Dolphins (32) have more deferrals.
During his news conference Tuesday, Bill Belichick addressed the philosophy of deferring the opening kick.
"I think obviously if you take the ball at the beginning of the game, you have a chance to get one more possession in the first half," he said. "If you take the ball at the beginning of the second half, you have a chance to get one more possession in the second half."
In short, he'd rather have the ball in the second half.
A quick look at the third quarter shows just how significant that has been. The Patriots have outscored the opposition141-50 in the third quarter. That means in the first and third quarters combined, the Patriots have a plus-86 scoring margin. Suddenly, complaints about the first quarter appear far less significant.
Belichick seemingly tried to downplay the significance of the strategy.
"Either way, if you get it this half, they get it that half," he said. "It's not like you're actually stealing something from somebody, it's just a question of if you win the toss and even have a preference then what's your preference? ... I don't think it's that big of a deal.
Belichick may say it's not a big deal, but that might be because his opponents give him what he wants anyway. Deferring isn't for everyone. The Colts have done it just once in the past four seasons, while the Falcons still haven't deferred since the rule was put in place.
Opponents have deferred just 15 of 41 times against the Patriots since 2008.
Does it matter? Since 2008, the Patriots are 11-5 when receiving the opening kickoff compared to 37-11 when receiving to begin the second half.
Jeremy Lundblad is a senior researcher with ESPN Stats & Information. He provides statistical analysis for ESPNBoston.com.


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Dec 21
Live from The World Famous Stone Pony on the last day of the existence December 21st 2012 we bring you: ::::::::::::::::::::Nightmare Before Christmas:::::::::::::::::::: 50 artists displaying & selling work LIVE BURLESQUE via Ink & Paint Burlesque Lily Stitches - Luna Chase - Vonka Romanov - Murder Nurse 7 bands including The Shady Street Showband performing the score of The Nightmare Before Christmas with a 20 person zombie chorus! The Shady Street Show Band, Boy Meets Machine, Midnight Mosaic +more! 15 PUDDING WRESTLING MATCHES Central Jersey Pudding Wrestling
Oct 31
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BOY MEETS MACHINE @ The Middle East in Cambridge Mass!!
Jul 26
BOY MEETS MACHINE @ Crocodile Rock Cafe in Allentown PA
Bio: Boy Meets Machine began in 2008 with two cold-blooded-country boys (singer and bassist, Joel Monet and guitarist, Mike Mentz) relocating from Huntsville, Alabama to Atlanta, Georgia, where they entered the burgeoning local music scene Hell-bent on success. They quickly formed the first incarnatio...See Full Bio

subset: commoncrawl


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We stayed in one of the deluxe rooms, complete with a fireplace and I would recommend one of these rooms if you can. The room was spacious, the bathroom huge and the bed was massive and very comfortable. The pool area was fun to relax in and the hot spa was a nice treat after the minus 28 degrees weather. The ski stop is about 2 hotels up from the Delta Banff and easy to get to. The hotel provides a ski lock up storage in the carpark which you can access with your room key. The staff were very helpful.
- Official Description (provided by the hotel):
- This fine Banff resort welcomes you to experience a restful stay amid the grand surroundings of the Canadian Rocky Mountains. This intimate boutique Banff hotel offers 99 guestrooms and suites that are spacious and thoughtfully appointed. Guests of the Delta Banff Royal Canadian Lodge can enjoy fine dining in the Evergreen Restaurant one of Banffs best kept secrets, or a visit to the Grotto Spa. Relax, unwind, and rejuvenate with the soothing sounds of water flowing peacefully over the rundle rock waterfall in the hot mineral pool and luxurious whirlpool. Also a great place for a meeting in Banff! ... more less
- Reservation Options:
- TripAdvisor is proud to partner with Booking.com, Orbitz, Marriott, Expedia, Hotels.com, Hotwire, Priceline, Odigeo, Agoda, Travelocity, TripOnline SA, Cheap Tickets and Jetsetter so you can book your Delta Banff Royal Canadian Lodge reservations with confidence. We help millions of travelers each month to find the perfect hotel for both vacation and business trips, always with the best discounts and special offers.
- Also Known As:
- Delta Banff Royal Canadian Hotel Banff
- Banff Delta


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Hours: Tuesday-Thursday open 6-10 p.m.
Friday-Saturday open 6-11 p.m.
street parking
Price: $$ ($10-$20)
Just up the street from Ansley Mall, Tierra's provocative pan-Latin fusion cuisine is a welcome reprieve in an area of town notorious for the uneven quality of its restaurants. Cheese pupusas, trout relleno and beef tenderloin in tomatillo sauce are winning menu staples. Well-crafted desserts, competent service and a succinct wine list see meals here to harmonious completion.
Price: $$ ($10-$20)


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Friendly Frog Cookies
Additional Information
Step 1
Prepare and roll out dough. Cut 1 teddy bear face and 2 medium heart cookies for each treat. Bake and cool. Cover cookies with thinned royal icing; let dry on waxed paper-covered boards.
Step 2
Attach face to 2 hearts with tip 12 and full-strength royal icing. Pipe tip 10 ball eyes (flatten and smooth with finger dipped in cornstarch). Pipe tip 5 outline eyelids, tip 4 dot pupils and outline mouth. Pipe tip 12 front legs. Let dry.
*Combine Leaf Green with Lemon Yellow for green shown.
Leaf Green Icing Color
Lemon Yellow Icing Color
Black Icing Color
Meringue Powder
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Waxed paper
The ball shape makes bold borders and is the first step to learn for figure piping. Vary the basic look by adding stars, dots or spirals on the ball shapes.
Pipe dots for flower centers, faces, figure piping and border effects. When making large dots, lift the tip as you squeeze to allow icing to fill out completely.
Characters or designs are often outlined first, then piped in with stars or zigzags. Outlines can also be used for facial features.
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Add name tags to these perkily potted aviaries to use as personalized place markers. Shape birdhouses by reshaping cookies created with a Square Crinkle Comfort Grip Cutter.
Send spirits soaring with these lively bee and butterfly pops. Tint cookie dough yellow and create the winged creatures using Bug Buddies Metal Cutter Set, piped icing, and candy details.
Tastier and more fun than animal crackers from a box! These cute shapes are easy when cookie dough is molded in the Jungle Animals Fondant and Gum Paste Mold then decorated with colorful Rainbow Nonpareils.


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Is bigger better for the ACC?
Not a great deal changed on the field in college football this past weekend, where Oklahoma solidified its hold on No. 1 with a win over Florida State. Off the field? Yeah, about that. It appears Florida State will soon have more company in the ACC after the conference approved Pittsburgh and Syracuse as new members. Is this the biggest domino to fall thus far in conference realignment? More: Rank the Top 25 in college football.
- "Geez, I go out to Los Angeles to watch Syracuse play USC and I come back to find out Syracuse is now a member of the ACC. Didn't see this one coming." -- SN commenter gsgriffin4
- "I think what's important here is we may finally be done listening to Big East fans talk about how much better they are in basketball than everyone else. It's a good day." -- SN commenter sharar09
Which school is a bigger prize?
When it comes to January road trips, we're not sure either Pittsburgh or Syracuse is much of a prize, but which school is a bigger addition?
Where does the ACC go from here?
Rumors already are swirling about the ACC adding Connecticut and Rutgers to reach the apparently magical total of 16 teams.
Biggest move to date?
Colorado, Nebraska and Utah are the only schools actually competing in new conferences at the moment, but Pitt and Syracuse joined Texas A&M in securing the blessing of new partners.
What about the bigger picture?
The height of greed and hypocrisy? A fresh look and new rivalries? Much ado about nothing that matters? What's your take on the state of conference realignment?
Which leftovers go bad first?
In addition to rumors about UConn and Rutgers, reports have talks again heating up between the Pac-12 and Texas and Oklahoma.


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illustrating "tweens"….
Monday, July 25th, 2016 | Fashion Illustrations, Fashionable DIY & Crafts | No Comments
Somewhere between adorable and beautiful reside those amazing creatures know as "tweens"…
Today I'm featuring another quick tutorial depicting an angelic tween model in an outfit of my own imagination! Her sheer skirt over fuschia leggings presents an interesting painting challenge….let's begin!
Step 1: Start with a flesh colored watercolor pencil and loosely sketch your figure….
Add some color swatches to create a working palette if you like!
Step 2: Add some facial details with your watercolor pencil…just make light smudges to represent her eyes, mouth and nose!
Step 3: Add light washes of color to create a sheer skirt over leggings…..start with the lightest pink then add more saturated tones of fuschia. Mix a tiny bit of white gouache with the fuschia to create gradual variations in the thickness of the leggings under the skirt. Be very loose and sketchy with this technique to give the illusion of a sheer fabric over opaque leggings.
Step 4: Add details to the skirt with your pencils such as tiny flowers…. then with bolder strokes of a grey or charcoal pencil outline small areas of her skirt such as tiny gathers in the fabric…..
Step 5: Continue to add finer details such as facial features or strands of hair with your pencils….
And your illustration is complete! Enjoy!!
Read More »
vintage beauties….a watercolor tutorial
Friday, July 22nd, 2016 | Fashion Illustrations, Fashionable Decor, Fashionable DIY & Crafts, In the Shop | No Comments
Happy Friday, lovelies! Summer weekends inspire watercolor tutorials featuring gorgeous girls of summer like these vintage beauties I found on Pinterest! I encourage you to be experimental and bold with your color choices….let's begin!
First, using a flesh colored watercolor pencil, create a loose sketch. If you aren't comfortable drawing freehand trace the figures using a light box or sunny window.
Next, add light washes of watercolor….
Start with neutrals then add pops of blue, turquoise and fuschia where you might normally shade in greys or browns….
Finally, add details with bold strokes of colored pencils….
Have fun with unexpected color combinations!
You will love the result!
My Girls of Summer and Vintage Beauties prints are available now in my Etsy Shop! Enjoy!Read More »
Be Your Own Fashion Artist Coloring Book….Debut!
Wednesday, July 20th, 2016 | Coloring Books, Fashionable DIY & Crafts, In the Shop | No Comments
Hot off the presses, my coloring book is here!
Over 100 pages of flowers, lovely ladies, hip accessories and whimsical textile illustrations await your coloring and collaging skills! Each illustration is duplicated three times so you don't have to worry about making a mistake. Color, collage, create!
For a full product description please check out my listing on Etsy or Amazon….And remember, I would love to see your finished work! Use #beyourownfashionartist on FB or Instagram!Read More »
new prints in the shop!
Monday, July 18th, 2016 | Fashion Illustrations, Fashionable Decor, In the Shop | No Comments
Happy Monday! These long hot days of summer have me obsessed with wide brimmed floppy hats and gauzy skirts…
So I've created a couple of summery prints just added to Etsy:
"Girl in a Pink and White Striped Hat"….
and "Girl in a Pale Blue Hat"…….I thought I'd show you images of how these works came to be!
I always start with light flesh watercolor pencil outlining the form…..
Then add washes of watercolor….
Followed by more detailed pencil work….
I have left a lot of the pencil work and under drawing visible in these two prints to give them a vintage yet timeless feeling!
The gauzy skirts flow right off the page….Enjoy!!!Read More »
On my drawing table….
Friday, July 15th, 2016 | Brides | No Comments
Folk Art Brides on mini canvases…..
Sweet!Read More »


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I tried to read through the whole jvmti documentation and I didn't find a solution for my problem.
I want to get the name of the class/file that is used in the command line to call the program:
java -agentpath:<pathToAgent> <calledJavaProgram>
In upper case I want to get the name of < calledJavaProgram >.
GetSourceFileName(jclass klass,...) gets me only the name of the "klass", that is set in the parameterlist, but since I started the program I even don't know this one ... right?
Are there (other) ways to get this name?
Thx for your help Markus G.


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Visit Edmunds.com for a complete listing of local car dealerships in Knoxville, Tennessee. Find the best deal on your next vehicle with online discount price quotes on car, truck, SUV, and minivan models. With the ability to compare prices on new and used vehicles in Knoxville, Edmunds.com makes the car buying process convenient and cost-effective. Search for car dealerships in Knoxville, Tennessee with our comprehensive dealership network and avoid the common hassles associated with car shopping.
Non Display Review Name "How lucky KIA is to have a salesman like Ron Yelen. Once I was a top supervisor for about 1200 Soldier's.I recognize right away their capabilities wi"... Read more Review by: sgmglass


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Julia Joyce (born 14 June 1998) is an actress, known for her three appearances as a younger version of Billie Piper's characters in Doctor Who ("Father's Day"), Ruby in the Smoke and Mansfield Park. She is also the younger sister of the act...ress, model and Petits Filous advert star Lucy Joyce.
Connect any celebrity with Julia Joyce to see how closely they are linked... romantically!


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Festive Spanish Baroque villancicos, ornate cantatas, and lively instrumental music exported to 18th-century Central & South America. Works by Durán, Jurusalem, Torres, Iribarren, and others.
With soprano Jessica Petrus, mezzo soprano Catherine Hedberg, and Baroque guitarist Eloy Cruz
The 2016-2017 Season
Submitted by danryan on Thu, 06/23/2016 - 7:57am
Programming for our 2016-17 season focuses on a topic that is as relevant today as it was in the 18th century: migration. The migration of musicians and their music in the Old and New Worlds shaped the musical environments in which these musicians found themselves, changing the course of music history.
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Hi girls!
I'm feeling a bit better about the miscarriage now so figured I'd stop in and say Hi! I hope you are all doing well and some of you must be approaching the 2nd tri, how exciting!!
I'm still spotting a bit but the large part of the m/c is over. I had one really bad/scary day but otherwise it's been like a period. I'm finally looking less pregnant and fit back into regular pants yesterday which was nice. DH thinks I should try to lose some weight which he's probably right, but I'm feeling lazy about it! LOL!
The kids are doing great! Livy's birthday is in just 2 weeks. We are having her party on the 1st so excited about that! Ethan is crazy and driving me nuts so very glad I have more patience (no more hormones).
I keep wondering when/if I'll know if I'm ready to try for another baby or not. For any of you who went through a m/c how long until you felt ready to try again? I wonder if I'm weird for not wanting to try right away?
Anyway - how are all of you? I haven't been lurking on here, so update me!


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Tie Shoe..put on sock?
Discussion in 'Hip Replacement Recovery Area' started by RollsRoyce, Feb 28, 2011.
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The LHG team held a very successful, action-packed sprint at the Huawei/Hisilicon facilities in Shenzhen, China on July 11-14. The sprint was well attended by Linaro and LHG member company engineers, and pulled in a lot of interested local engineers from Hisilicon, MStar, and ZTE.
The key sprint activities included:
There was an Open House session on Wednesday afternoon (3-5pm) where prospective LHG members (Spreadtrum and Rockchip) witnessed the LHG team in action. The LHG engineers gave five demos and walked the visitors through each of their demos. The visitors were visibly impressed to see a total LHG team effort for the demos and the high level of engagement and infectious enthusiasm in the team.
Finally on Thursday, there was a meeting of the LHG member companies who are also participating in the China TVOS working group with the CTO from the China state agency (SAPPRFT) – Mr. Steve Sheng. The meeting focused on how LHG can participate and contribute to the TVOS project and was very positive.
I was deeply gratified to see a high level of commitment to engineering excellence exhibited by the Linaro and member assignee engineers throughout the week. A big thank you to all for making it a tremendous success!
A special note of thanks to our hosts Huawei/Hisilicon for the superb meeting facilities and taking care of logistics, transportation, meals, etc. Greatly appreciated!
Created in April 2016, devicetree.org was set up by Linaro to make device tree a properly managed and supported standard targeting multiple operating systems. While the concept devicetree has been around for some time, devicetree.org is the first to put a process in place to ensure standardisation and consistency is captured into a specification which will also evolve with the technology. Read more on the devicetree.org site]]>
A Little Bit of History
LAVA ran its first job at 15:48:58 on Wednesday 27th July 2011 on a Pandaboard. The job was submitted by Frans Gifford, and now, almost exactly 5 years later, we have processed job number 1,000,000.
When LAVA first went live we were running around 20 jobs a day on average. Compare this with today where we run around 2,000 jobs per day on 40 different device types, some physical and some virtual, with a total of 129 device instances. Don't forget, this is just the main production instance. We also have the LNG, TCWG, PMWG and OpenStack micro-instances.
To illustrate the difference between the start of LAVA and the present day, here are two animations, one from the first month of execution and the other covering just the last week, and the 1,000,000th job. In the animation, each spur from the centre represents a device type (e.g. panda and beaglexm), each spur from that is an active device instance, the number on that spur is the job ID, and the little figures flashing lasers at the devices are the job submitters, either human or, more frequently, automated submission bots.
We created these animations using a tool called 'gource', which was actually designed to visualise the usage of source code control systems such as 'git' over time. I cannot claim sole responsibility for this, since it was Paul Larson, the original LAVA Tech Lead, who first ran it for our first San Francisco event, then known as LDS, in February 2012. I've modified and improved the database extraction, but the original concept is Paul's.
So, when will we run job number 2,000,000? Well, what may happen is that we will actually hit 1,000,000 again because we're going to be switching over to LAVA V2 in the next 12 months, and when we have completed that transition we may well start the jobs back at 1, because the results format of the new LAVA is significantly different from V1. We will maintain the old database for historical purposes, but we're envisaging a clean start.
What's so special about V2? That is worthy of a blog post all on it's own, but one of the main advantages we've seen is that it is significantly more efficient for deployment and test runs because test writers have much finer control over what to do when actions fail. If we take into account the efficiency and the rate of job submission growth, along with our projected growth in the number of Lab devices, we could well see job 1,000,000 within the next three years.
I'll keep you posted.
To find out more about LAVA, please follow this link.
Linaro 16.06 release is now available for download. See the detailed highlights of this release to get an overview of what has been accomplished by the Working Groups, Landing Teams and Platform Teams. We encourage everybody to use the 16.06 release. To sign-up for the release mailing list go here: https://lists.linaro.org/mailman/listinfo/linaro-release
This post includes links to more information and instructions for using the images. The download links for all images and components are available on our downloads page:
The Android-based images come in three parts: system, userdata and boot. These need to be combined to form a complete Android install. For an explanation of how to do this please see:
If you are interested in getting the source and building these images yourself please see the following pages:
The Ubuntu-based images consist of two parts. The first part is a hardware pack, which can be found under the hwpacks directory and contains hardware specific packages (such as the kernel and bootloader). The second part is the rootfs, which is combined with the hardware pack to create a complete image. For more information on how to create an image please see:
With the Linaro provided downloads and with ARM's Fast Models virtual platform, you may boot a virtual ARMv8 system and run 64-bit binaries. For more information please see:
The Debian-based images consist of two parts. The first part is a hardware pack, which can be found under the hwpacks directory and contains hardware specific packages (such as the kernel and bootloader). The second part is the rootfs, which is combined with the hardware pack to create a complete image. For more information on how to create an image please see:
More information on Linaro can be found on our websites:
Also subscribe to the important Linaro mailing lists and join our IRC channels to stay on top of Linaro developments:
UPCOMING LINARO CONNECT EVENTS: LINARO CONNECT Las Vegas 2016
Linaro Connect Las Vegas 2016 will be held September 26-30, 2016. More information on this event can be found at: http://connect.linaro.org/las16/
There are different views of what "idle" means. One may think about CPUs and how to prevent wasting power when CPUs become idle, but in fact, idle management of platforms reaches far beyond that.
On many platforms there is a huge amount of other resources besides the CPUs, which also are able to enter low power states. Often these resources could be idle even when the CPUs are not.
In this article I have chosen to focus on platform resources in general and describe some of the available generic methods of deploying idle management for them. With the goal to prevent wasting power of course.
Runtime PM vs system PM
The system PM framework enables platforms to enter a system wide low power state, which prevents power being wasted when the entire platform is idle. This happens for example when the lid is closed on a laptop computer or when the screen is turned off on an Android phone. Generally, under these circumstances, quite a long wake-up latency for the platform is accepted by the user, which allows the platform to select a deep low power state to consume as little power as possible.
However, in many scenarios it is not an option to enter a system wide low power state, as some parts of the platform are being used. By deploying the so called runtime PM support, the idle devices of the platform can enter lower power states independently of the other non-idle devices of the system, further preventing the platform from wasting power.
As system PM and runtime PM deals with different scenarios for idle management, deploying both is important to prevent wasting power for a platform.
Historically, system PM and runtime PM have been treated as two orthogonal PM frameworks, which has led to issues and unoptimized behaviors when combining them. Improvements have been made on this field and the more important ones are described below.
Deploy system PM via the runtime PM centric approach!
It's quite common that the operations carried out to put a device into low power state, which are performed during system PM suspend and runtime PM suspend, are very similar – sometimes even the same. Vice versa applies when powering on a device.
In these cases, a subsystem/driver can easily deploy system PM support by using the so called runtime PM centric approach. Simply add runtime PM support and then assign a pair of the system PM callbacks to the pm_runtime_force_suspend|resume() helper functions – that's it!
Below is the typical code needed for driver/subsystem to deploy system PM via the runtime PM centric approach:
static const struct dev_pm_ops mydrv_dev_pm_ops = {
SET_RUNTIME_PM_OPS(mydrv_ runtime_suspend,
As mentioned earlier, the pm_runtime_force_suspend|resume() helper functions take care of some common issues due to combining runtime PM and system PM, but they also re-use the runtime PM callbacks to power on/off a device, hence why this is called the runtime PM centric approach.
For devices where system PM and runtime PM slightly differs, perhaps because of different wake-up settings or a demand to suspend a request queue only in the system PM case, the subsystem/driver can still benefit from using the pm_runtime_force_suspend|resume() helper functions.
Instead of assigning the system PM callbacks to the helper functions, the subsystem/driver may assign its own implemented system PM callbacks to deal with the additional system PM operations. From within these callbacks it invokes the corresponding pm_runtime_force_suspend|resume() function to put its device into low power state.
To get some more examples of how the pm_runtime_force_suspend|resume() helpers are being used, run the following git command from within your local Linux kernel git tree, "git grep pm_runtime_force_".
PM domains
It's quite common that parts of a platform can be powered on/off separately from other parts. If each part would consist of only a single device, runtime PM and system PM of devices would be sufficient to deal with idle management. Although, there exists more complex topologies than this.
To not waste power on these platforms, we need to be able to put parts, which may involve a collection of devices, into low power states in a controlled manner. That is one of the reasons why the concept of a PM domain has been introduced to the Linux kernel. The PM domain allows devices to be managed not only by their subsystems/drivers, but also through the optionally associated PM domain structure.
The generic PM domain
To solve common issues regarding how to deal with PM domains, the so called generic PM domain (aka genpd) has been invented.
Through DT, the PM domain topology of a platform can be described as well as the connection of the devices. Genpd provides the APIs to allow users to dynamically build this topology in runtime. It also allows devices to be grouped into PM domains and it supports methods to manage sub-domains and master-domains. In combination with runtime PM, system PM and the device PM QoS frameworks, genpd provides a generic solution for idle management of devices and PM domains. The goal is to prevent platforms from wasting power!
This is an example of a PM domain topology of a SoC.
To describe the topology from the picture above in DT, this is typically what needs to be encoded in the DTS.
pm_domain: power-controller@12340000 {
compatible = "foo,power-controller";
reg = <0x12340000 0x1000>;
#power-domain-cells = <1>;
pm_subdomain: power-controller@12341000 {
compatible = "foo,power-controller";
reg = <0x12341000 0x1000>;
power-domains = <&pm_domain 0>;
#power-domain-cells = <1>;
dev0@12350000 {
compatible = "foo,i-leak-current";
reg = <0x12350000 0x1000>;
power-domains = <&pm_domain 0>;
dev1@12351000 {
compatible = "foo,i-leak-current";
reg = <0x12351000 0x1000>;
power-domains = <&pm_domain 0>;
dev2@12356000 {
compatible = "bar,i-leak-current";
reg = <0x12356000 0x1000>;
power-domains = <&pm_subdomain 0>;
dev3@12356100 {
compatible = "bar,i-leak-current";
reg = <0x12356100 0x1000>;
power-domains = <&pm_subdomain 0>;
dev4@12356200 {
compatible = "bar,i-leak-current";
reg = <0x12356200 0x1000>;
power-domains = <&pm_subdomain 0>;
dev5@12356300 {
compatible = "bar,i-leak-current";
reg = <0x12356300 0x1000>;
power-domains = <&pm_subdomain 0>;
Did you know this about genpd?
The genpd has been around in the Linux kernel for quite a while, as it was introduced in version 3.1. From version 3.18, Linaro actively started contributing to an evolution of its code and now the community is steadily growing as can be seen in the below picture.
Deploying support for genpd for a platform is often easy, although to take full advantage of genpd's idle management through runtime PM, each device within the PM domain must have a corresponding subsystem/driver deploying runtime PM support. That's because genpd monitors devices' runtime PM status to understand when all devices within the same PM domain become idle. At that point, it tries to power off the PM domain to decrease the consumed power for the platform. On the opposite side, when a device is requested to be powered on via runtime PM, genpd makes sure to also restore power to the corresponding PM domain.
To enable platforms to execute specific operations while powering a PM domain on/off, genpd invokes the optional ->power_on|off() callbacks, if they have been assigned by the user.
Powering off a device and its PM domain prevents the platform from wasting power. However, doing this might in some cases introduce a request latency, as powering off/on a device and its PM domain, could consume a non-neglectable time. That means, when there's a new request to handle and if the device and its PM domain needs to be powered on, the request could be affected by an initial latency.
To address scenarios where certain latency constraints must be guaranteed, genpd provides the option to use the genpd governor. The governor makes use of the per device PM QoS framework, which allows users to set so called wake-up latency constraints for devices. An attempt to power off a device or its PM domain may thus be aborted by genpd, unless the governor reports that the validation of the latency constraint is accepted.
Ongoing work related to genpd and idle management
Optimize system PM suspend/resume support in genpd
Genpd may power on idle devices during the system PM suspend sequence. If a device is already in its proper low power state, the power on operation obviously becomes unnecessary as the device needs to be put back into low power state shortly after. This behaviour wastes some power and increases the system PM suspend time.
Moreover, genpd unnecessarily powers on devices in the system PM resume sequence. Regardless of whether the device could have remained in a low power state, it becomes powered on. Even if it shortly after becomes powered off, this behaviour wastes some power and increases the system PM resume time.
To optimize this behaviour, the decision to power on a device during the system PM sequence should be deferred to its subsystem/driver.
A unified solution to manage idle across all kind of devices, including CPUs
The linux kernel has two distinct ways of managing idle in runtime. The CPUIdle framework for CPUs and for other devices, runtime PM in combination with genpd. In addition, CPUIdle isn't scaling well for multi-cluster SMP systems and heterogeneous systems like big.LITTLE.
To manage idle of CPUs for SoCs with this hierarchical structure, we are trying to extend runtime PM and genpd to also cover CPUs. Genpd already provides most of the needed building blocks to deploy this solution, but another important effect is that we get a unified solution to manage idle across all kind of devices.]]>
In this article we explain how the CoreSight framework found in the Linux kernel has been integrated with the standard Perf core, both at the kernel and user space level. In the latter part the newly introduced Open CoreSight Decoding Library (OpenCSD) is used to assist with trace decoding. The topic of trace decoding with openCSD will be covered in an upcoming post.
All examples presented in this post have been collected on a juno-R0 platform using code that is public and accessible to everyone.
The standard Perf core is a performance analysis tool found in the Linux kernel. It comes with a complement user space tool, simply called perf, that provides a suite of sub-commands to control and present trace profiling sessions. Perf is most commonly used to access SoC performance counters, but over the years it has grown well beyond that and now covers tracepoints, software performance counters and dynamic probes.
The perf core is generic and caters to many architectures. To hide variations between HW implementation and profiling metrics the concept of Performance Monitoring Unit (PMU) is used. A PMU is a structure providing a well defined set of interfaces that PMU drivers implement in order to carry action on behalf of the Perf core. The actions carried out the by the PMU drivers are not relevant to the Perf core itself, as long as the semantic of the API is respected.
Every time a process is installed on a CPU for execution, the scheduler invokes the Perf core. From there Perf will see if any event is associated with that process and if so, the PMU API performing HW specific operations is invoked. The same happens when the process is removed from a CPU. That way statistics and performance counters are collected for that process only and aren't impacted by other activities concurrently happening in the system. Traces collected during a session are transferred to user space using a mmap'ed area and made available to users in the perf.data file. The latter is then read by the various perf sub-command for rendering in human readable format.
Integrating the CoreSight drivers with the Perf core was advantageous on many fronts. On the kernel side it streamlined the configuration of trace sessions – with hundreds of parameters per CPU this was certainly not something to pass on. It also offered a way to easily transfer massive amounts of trace data to user space with little overhead. In user space the metadata pertaining to each trace session could be embedded in the perf.data file and perf sub-commands like report and script used to decode trace data. Last but not least most of the upstream code can be re-used in the PMU abstraction.
To bridge the gap between the CoreSight framework and the Perf core, CoreSight tracers (ETMv3/4 and PTM) are modelled as PMUs. At boot time the newly introduced function etm_perf_init() registers an etm_pmu with the perf core:
#define CORESIGHT_ETM_PMU_NAME "cs_etm"
static struct pmu etm_pmu;
static int __init etm_perf_init(void)
int ret;
etm_pmu.capabilities = PERF_PMU_CAP_EXCLUSIVE;
etm_pmu.attr_groups = etm_pmu_attr_groups;
etm_pmu.task_ctx_nr = perf_sw_context;
etm_pmu.read = etm_event_read;
etm_pmu.event_init = etm_event_init;
etm_pmu.setup_aux = etm_setup_aux;
etm_pmu.free_aux = etm_free_aux;
etm_pmu.start = etm_event_start;
etm_pmu.stop = etm_event_stop;
etm_pmu.add = etm_event_add;
etm_pmu.del = etm_event_del;
etm_pmu.get_drv_configs = etm_get_drv_configs;
etm_pmu.free_drv_configs = etm_free_drv_configs;
ret = perf_pmu_register(&etm_pmu, CORESIGHT_ETM_PMU_NAME, -1);
if (ret == 0)
etm_perf_up = true;
return ret;
Calling perf_pmu_register() creates a new PMU with the characteristics found in the struct pmu given as a parameter. When a successful registration has completed the new PMU can be found alongside the other PMUs catalogued at boot time:
linaro@linaro-nano:~$ ls /sys/bus/event_source/devices/
breakpoint cs_etm software tracepoint
linaro@linaro-nano:~$ ls /sys/bus/event_source/devices/cs_etm
cpu0 cpu1 cpu2 cpu3 cpu4 cpu5 format perf_event_mux_interval_ms power subsystem type uevent
The astute reader will notice that cpu[0… 5] are not part of the typical sysFS entries associated with PMUs, and they will be correct. Upon successful registration with the CoreSight core, the ETMv3/PTM and ETMv4 drivers create a symbolic link between their sysFS entries and the new cs_etm PMU, allowing the Perf user space API to quickly retrieve the metadata associated with a tracer:
linaro@linaro-nano:~$ ls -l /sys/bus/event_source/devices/cs_etm/cpu0
lrwxrwxrwx 1 root root 0 Jun 1 20:19 /sys/bus/event_source/devices/cs_etm/cpu0 -> ../platform/23040000.etm/23040000.etm
linaro@linaro-nano:~$ ls /sys/bus/event_source/devices/cs_etm/cpu0/trcidr/
trcidr0 trcidr1 trcidr10 trcidr11 trcidr12 trcidr13 trcidr2 trcidr3 trcidr4 trcidr5 trcidr8 trcidr9
linaro@linaro-nano:~$ ls /sys/bus/event_source/devices/cs_etm/cpu0/mgmt/
trcauthstatus trcdevid trclsr trcpdcr trcpidr0 trcpidr2 trctraceid trcconfig trcdevtype trcoslsr trcpdsr trcpidr1 trcpidr3
In user space integration is done around three tools: perf record, perf report and perf script, which are the perf sub-commands we have been referring to. The first deals with event configuration and creation while the latter two assist in rendering trace data collected during a session in a human readable format.
Integration in the perf record sub-command is done by providing an architecture specific function that return a struct auxtrace_record. As with the kernel PMU abstraction the auxtrace_record structure allows the generic core to perform architecture-specific operations without losing genericity. That way it is possible to process traces data generated by IntePT and CoreSight without changing anything to the common core.
struct auxtrace_record *cs_etm_record_init(int *err)
struct perf_pmu *cs_etm_pmu;
struct cs_etm_recording *ptr;
cs_etm_pmu = perf_pmu__find(CORESIGHT_ETM_PMU_NAME);
ptr->cs_etm_pmu = cs_etm_pmu;
ptr->itr.parse_snapshot_options = cs_etm_parse_snapshot_options;
ptr->itr.recording_options = cs_etm_recording_options;
ptr->itr.info_priv_size = cs_etm_info_priv_size;
ptr->itr.info_fill = cs_etm_info_fill;
ptr->itr.find_snapshot = cs_etm_find_snapshot;
ptr->itr.snapshot_start = cs_etm_snapshot_start;
ptr->itr.snapshot_finish = cs_etm_snapshot_finish;
ptr->itr.reference = cs_etm_reference;
ptr->itr.free = cs_etm_recording_free;
ptr->itr.read_finish = cs_etm_read_finish;
*err = 0;
return &ptr->itr;
return NULL;
Among other things, functions provided to the struct auxtrace_record deal with how to find tracer specific metadata, the presentation and formatting of the metadata in the perf.data file along with specifics related to the size and mapping of the ring buffer shared between the kernel and user space. That ring buffer is then used to retrieve trace data from the kernel.
The decompression and rendering of trace data is done in the report and script utilities. The process starts by reading the perf.data file and parsing each of the events that were generated during a trace session. The AUXTRACE_INFO and PERF_RECORD_MMAP2 are especially important. The first event carries a wealth of information about how the tracers were configured, the so called metadata, and a list of offsets in the perf.data file where lumps of trace data are located. These offsets are recorded for later processing.
PERF_RECORD_MMAP2 events carry the name and path of the binary and libraries that were loaded/executed during the trace session. Those are commonly called Dynamic Shared Object, or DSO. Having a handle on the DSOs is important for trace decoding since some branch point don't carry the destination address, only that the branch point was taken or not. In those cases the code needs to be read to find out where execution resumed.
Once all that information has been tallied decoding of the trace data can begin. The process is done by feeding the previously recorded trace data offsets to the decoder. The decoder is an instantiated object provided by the openCSD companion library. It decodes trace data lumps in steps, calling a user provided callback function with each successful round .
Un-synthesised output will look like this:
mpoirier@t430:~/work/linaro/coresight/bkk16/jun01-kernel$ ../../kernel-cs-pm/tools/perf/perf report –stdio –dump
. … CoreSight ETM Trace data: size 162416 bytes
0: I_ASYNC : Alignment Synchronisation.
12: I_TRACE_INFO : Trace Info.
17: I_TRACE_ON : Trace On.
18: I_ADDR_CTXT_L_64IS0 : Address & Context, Long, 64 bit, IS0.; Addr=0xFFFFFFC000531720; Ctxt: AArch64,EL1, NS;
28: I_ATOM_F2 : Atom format 2.; NE
29: I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0xFFFFFFC000536038;
39: I_ATOM_F2 : Atom format 2.; EE
40: I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0xFFFFFFC0005366CC ~[0x166CC]
43: I_ATOM_F1 : Atom format 1.; E
44: I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0xFFFFFFC000531BC0 ~[0x11BC0]
48: I_ATOM_F3 : Atom format 3.; NEE
49: I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0xFFFFFFC000531F54 ~[0x11F54]
52: I_ATOM_F1 : Atom format 1.; E
53: I_ADDR_L_32IS0 : Address, Long, 32 bit, IS0.; Addr=0x0016BB60;
58: I_ATOM_F3 : Atom format 3.; NEE
59: I_ATOM_F3 : Atom format 3.; NNE
60: I_ATOM_F6 : Atom format 6.; EEEEEE
61: I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0x0016BBF4 ~[0x1F4]
64: I_ATOM_F1 : Atom format 1.; E
65: I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0x0016BD44 ~[0xBD44]
68: I_ATOM_F3 : Atom format 3.; NNE
69: I_ATOM_F1 : Atom format 1.; E
This raw trace packet output, ETMv4 in this case, is great for infrastructure debugging but of little value for system troubleshooting scenarios. These packets are further decoded by the OpenCSD library into a set of generic packets, describing core state and instruction ranges executed. The report and script commands will filter the packets they get back from the decoder and the packets related to executed instruction ranges will be accounted for and submitted for synthesis. In Perf terminology, the synthesis process deals with how decoded and relevant events are presented to users.
When using the report utility packets are synthesises to form a flame graph, where hot spots can be identified quickly:
mpoirier@t430:~/work/linaro/coresight/jun01-user$ perf report –stdio
[clip …]
# Children Self Command Shared Object Symbol
# …….. …….. ……. ……………. ………………….
4.13% 4.13% uname libc-2.21.so [.] 0x0000000000078758
3.74% 3.74% uname libc-2.21.so [.] 0x0000000000078e50
2.06% 2.06% uname libc-2.21.so [.] 0x00000000000fcaf4
1.65% 1.65% uname libc-2.21.so [.] 0x00000000000fcae4
1.59% 1.59% uname ld-2.21.so [.] 0x000000000000a7f4
1.50% 1.50% uname libc-2.21.so [.] 0x0000000000078e40
1.43% 1.43% uname libc-2.21.so [.] 0x00000000000fcac4
1.31% 1.31% uname libc-2.21.so [.] 0x000000000002f0c0
1.26% 1.26% uname ld-2.21.so [.] 0x0000000000016888
1.24% 1.24% uname libc-2.21.so [.] 0x00000000000fcab8
1.19% 1.19% uname ld-2.21.so [.] 0x0000000000008eb8
1.18% 1.18% uname libc-2.21.so [.] 0x0000000000078e7c
1.17% 1.17% uname libc-2.21.so [.] 0x0000000000078778
1.08% 1.08% uname libc-2.21.so [.] 0x0000000000078e98
1.04% 1.04% uname libc-2.21.so [.] 0x0000000000072520
1.04% 1.04% uname libc-2.21.so [.] 0x0000000000078e84
0.90% 0.90% uname libc-2.21.so [.] 0x0000000000072368
0.86% 0.86% uname libc-2.21.so [.] 0x00000000000fcac8
0.83% 0.83% uname libc-2.21.so [.] 0x0000000000071624
0.81% 0.81% uname ld-2.21.so [.] 0x00000000000084b4
0.80% 0.80% uname libc-2.21.so [.] 0x0000000000074900
0.80% 0.80% uname libc-2.21.so [.] 0x00000000000726c0
0.79% 0.79% uname libc-2.21.so [.] 0x0000000000078e54
0.79% 0.79% uname libc-2.21.so [.] 0x00000000000728d0
0.75% 0.75% uname libc-2.21.so [.] 0x0000000000078e74
The above shows that 4.13% of all the instruction ranges started in library libc-2.21.so at address 0x0000000000078758. Using the source code, the DSO file and an objdump utility it is possible to quickly identify the function that was referenced. It is important to keep in mind that flame graphs are generated using the entry point only. Nothing can be deduced about the path through the code that was taken after that.
From more accurate results it is suggested to work with the script command where a user supplied script can take advantage of all the information conveyed by synthesised events by way of the perf_sample structure. An example is the cs-trace-disasm.py script produced by Linaro:
FILE: /lib/aarch64-linux-gnu/ld-2.21.so CPU: 0
7f9175cd80: 910003e0 mov x0, sp
7f9175cd84: 94000d53 bl 7f917602d0 <free@plt+0x3790>
FILE: /lib/aarch64-linux-gnu/ld-2.21.so CPU: 0
7f917602d0: d11203ff sub sp, sp, #0x480
7f917602d4: a9ba7bfd stp x29, x30, [sp,#-96]!
7f917602d8: 910003fd mov x29, sp
7f917602dc: a90363f7 stp x23, x24, [sp,#48]
7f917602e0: 9101e3b7 add x23, x29, #0x78
7f917602e4: a90573fb stp x27, x28, [sp,#80]
7f917602e8: a90153f3 stp x19, x20, [sp,#16]
7f917602ec: aa0003fb mov x27, x0
7f917602f0: 910a82e1 add x1, x23, #0x2a0
7f917602f4: a9025bf5 stp x21, x22, [sp,#32]
7f917602f8: a9046bf9 stp x25, x26, [sp,#64]
7f917602fc: 910102e0 add x0, x23, #0x40
7f91760300: f800841f str xzr, [x0],#8
7f91760304: eb01001f cmp x0, x1
7f91760308: 54ffffc1 b.ne 7f91760300 <free@plt+0x37c0>
FILE: /lib/aarch64-linux-gnu/ld-2.21.so CPU: 0
7f91760300: f800841f str xzr, [x0],#8
7f91760304: eb01001f cmp x0, x1
7f91760308: 54ffffc1 b.ne 7f91760300 <free@plt+0x37c0>
FILE: /lib/aarch64-linux-gnu/ld-2.21.so CPU: 0
7f91760300: f800841f str xzr, [x0],#8
7f91760304: eb01001f cmp x0, x1
7f91760308: 54ffffc1 b.ne 7f91760300 <free@plt+0x37c0>
FILE: /lib/aarch64-linux-gnu/ld-2.21.so CPU: 0
Here we can see exactly the path a processor took through the code. The first field is the address in the DSO, the second the OPcode as found in the DSO at that specific address while the remaining of the line depicts an assembly language representation of the instructions as provided by objdump. Instructions on how to setup an environment capable of producing the above output can be found on the openCSD website.
In this post we presented the main elements used to integrate the CoreSight framework with the Linux Perf core. In kernel space CoreSight tracer configuration and control functions are folded in the PMU interface, allowing the Perf core to control trace generation the same way it does with any other system monitoring metrics. In user space the very valuable metadata, along with trace session blobs, are extracted from the perf.data file and submitted to the decoder for packet extraction. Different synthesis methods are offered depending on the level of details needed, i.e the popular flame graph is generated using perf report command while more detailed analysis can be rendered by python or perl scripts.
An upcoming post on this blog will feature the OpenCSD library in detail. It will introduce the different components, how these are used to decode trace, and the C++ and C APIs allowing integration with various standalone programs. The library example and test programs, which demonstrate using the library will also be presented.]]>
ARM servers are becoming increasingly common, making server technologies such as virtualization for ARM of growing importance. We present the first study(1) of ARM virtualization performance on server hardware, including multi- core measurements of two popular ARM and x86 hypervisors, KVM and Xen. We show how ARM hardware support for virtualization can enable much faster transitions between VMs and the hypervisor, a key hypervisor operation. However, current hypervisor designs, including both Type 1 hypervisors such as Xen and Type 2 hypervisors such as KVM, are not able to fully leverage this performance benefit for real application workloads. We discuss the reasons why and show that other factors related to hypervisor software design and implementation have a larger role in overall performance. Based on our measurements, we discuss changes to ARM's hardware virtualization support that can potentially bridge the gap to bring its faster VM-to-hypervisor transition mechanism to modern Type 2 hypervisors running real applications. These changes have been incorporated into the latest ARM architecture.
Despite the importance of ARM virtualization, little is known in practice regarding how well virtualized systems perform using ARM. There are no detailed studies of ARM virtualization performance on server hardware. Although KVM and Xen both have ARM and x86 virtualization solutions, there are substantial differences between their ARM and x86 approaches because of key architectural differences between the underlying ARM and x86 hardware virtualization mechanisms. It is unclear whether these differences have a material impact, positive or negative, on performance. The lack of clear performance data limits the ability of hardware and software architects to build efficient ARM virtualization solutions, and limits the ability of companies to evaluate how best to deploy ARM virtualization solutions to meet their infrastructure needs. The increasing demand for ARM-based solutions and growing investments in ARM server infrastructure makes this problem one of key importance.
Linaro, in collaboration with Columbia University, present the first in-depth study of ARM virtualization performance on multi-core server hardware. We measure the performance of the two most popular ARM hypervisors, KVM and Xen, and compare them with their respective x86 counterparts. These hypervisors are important and useful to compare on ARM given their popularity and their different design choices. Xen is a standalone bare-metal hypervisor, commonly referred to as a Type 1 hypervisor. KVM is a hosted hypervisor integrated within an existing OS kernel, commonly referred to as a Type 2 hypervisor.
The detailed results of this study are to appear in the 43rd International Symposium on Computer Architecture (ISCA), a first-tier academic conference for computer architecture.
Figure 1 depicts the two main hypervisor designs, Type 1 and Type 2. Type 1 hypervisors, like Xen, comprise a separate hypervisor software component, which runs directly on the hardware and provides a virtual machine abstraction to VMs running on top of the hypervisor. Type 2 hypervisors, like KVM, run an existing OS on the hardware and run both VMs and applications on top of the OS. Type 2 hypervisors typically modify the existing OS to facilitate running of VMs, either by integrating the Virtual Machine Monitor (VMM) into the existing OS source code base, or by installing the VMM as a driver into the OS. KVM integrates directly with Linux where other solutions such as VMware Workstation use a loadable driver in the existing OS kernel to monitor virtual machines. The OS integrated with a Type 2 hypervisor is commonly referred to as the host OS, as opposed to the guest OS which runs in a VM.
One advantage of Type 2 hypervisors over Type 1 hypervisors is the reuse of existing OS code, specifically device drivers for a wide range of available hardware. This is especially true for server systems with PCI where any commercially available PCI adapter can be used. Traditionally, a Type 1 hypervisor suffers from having to re-implement device drivers for all supported hardware. However, Xen, a Type 1 hypervisor, avoids this by only implementing a minimal amount of hardware support directly in the hypervisor and running a special privileged VM, Dom0, which runs an existing OS such as Linux and uses all the existing device drivers for that OS. Xen then uses Dom0 to perform I/O using existing device drivers on behalf of normal VMs, also known as DomUs.
Transitions from a VM to the hypervisor occur whenever the hypervisor exercises system control, such as processing interrupts or I/O. The hypervisor transitions back to the VM once it has completed its work managing the hardware, letting workloads in VMs continue executing. The cost of such transitions is pure overhead and can add significant latency in communication between the hypervisor and the VM. A primary goal in designing both hypervisor software and hardware support for virtualization is to reduce the frequency and cost of transitions as much as possible.
To evaluate the performance of ARM virtualization, we ran both microbenchmarks and real application workloads on the most popular hypervisors on ARM server hardware. As a baseline for comparison, we also conducted the same experiments with corresponding x86 hypervisors and server hardware. We leveraged University of Utah's CloudLab installation of hundreds of ARM 64-bit HP Moonshot m400 nodes and a plethora of x86 servers for our measurements. We compared ARM measurements with Intel Xeon 2.1 GHz ES-2450 CPUs in similar configurations of RAM, disk, network, and more. All network measurements were done with 10G isolated Mellanox networking equipment.
We designed and ran a number of microbenchmarks to quantify important low-level interactions between the hypervisor and the ARM hardware support for virtualization. A primary performance cost in running in a VM is how much time must be spent outside the VM, which is time not spent running the workload in the VM and therefore is virtualization overhead compared to native execution. Therefore, our microbenchmarks are designed to measure time spent handling a trap from the VM to the hypervisor, including time spent on transitioning between the VM and the hypervisor, time spent processing interrupts, time spent switching between VMs, and latency added to I/O.
To provide comparable measurements, we kept the soft-ware environments across all hardware platforms and all hypervisors the same as much as possible. We used the most recent stable versions available at the time of our experiments of the most popular hypervisors on ARM and their counterparts on x86: KVM in Linux 4.0-rc4 with QEMU 2.2.0, and Xen 4.5.0. KVM was configured with its standard VHOST networking feature, allowing data handling to occur in the kernel instead of userspace, and with cache=none for its block storage devices. Xen was configured with its in-kernel block and network backend drivers to provide best performance and reflect the most commonly used I/O configuration for Xen deployments. Xen x86 was configured to use HVM domains, except for Dom0 which was only supported as a PV instance. All hosts and VMs used Ubuntu 14.04 with the same Linux 4.0-rc4 kernel and software configuration for all
machines. A few patches were applied to support the various hardware configurations, such as adding support for the APM X-Gene PCI bus for the HP m400 servers. All VMs used paravirtualized I/O, typical of cloud infrastructure deployments such as Amazon EC2, instead of device passthrough, due to the absence of an IOMMU in our test environment.
We designed a custom Linux kernel driver, which ran in the VM under KVM and Xen, on ARM and x86, and executed the microbenchmarks in the same way across all platforms. Using this framework, we ran seven microbenchmarks that measure various low-level aspects of hypervisor performance.
KVM ARM Hypercall cost: 6,500 cycles
Xen ARM Hypercall cost: 376 cycles
As an example of our microbenchmarks, we measured the cost of a no-op hypercall, measuring a transition from the VM to the hypervisor and a return to the VM without doing any work in the hypervisor; in other words the bidirectional base transition cost of hypervisor operations. The Hypercall microbenchmark shows that transitioning from a VM to the hypervisor on ARM can be significantly faster than x86, as shown by the Xen ARM measurement, which takes less than a third of the cycles that Xen or KVM on x86 take.
We have analyze the true reasons for this difference in performance and developed and ran many more micro-level benchmarks, which can be found in the published paper about this work.
We also ran a number of real application benchmark workloads to quantify how well the ARM virtualization extensions support different hypervisor software designs in the context of more realistic workloads. The benchmarks we ran include a mix of widely-used CPU and I/O intensive benchmark workloads. For workloads involving a client and a server, we ran the client on a dedicated machine and the server on the configuration being measured, ensuring that the client was never saturated during any of our experiments. We ran these workloads natively and on both KVM and Xen on both ARM and x86, the latter to provide a baseline comparison.
Again, for an in-depth discussion of these results we refer you to the published paper, but we provide two examples here: First, the low hypercall performance of Xen vs. KVM on ARM, really only shows up in an isolated fashion in the hackbench results. The reason is that hackbench heavily utilizes the Linux scheduler, which results in a high amount of rescheduling virtual IPIs, and Xen ARM benefits from its low VM-to-hypervisor transition time for handling virtual IPIs.
Second, consider the latency-sensitive network benchmark TCP_RR. This benchmark sends a single byte back and forward between a client and the server running in the VM, and shows high overhead on all platforms. To understand where this overhead is spent, we used tcpdump to capture timestamps at various locations in the full software stack. These results showed us that the majority of the overhead spent on the incoming network path was between the physical machine running the VMs receiving a network packet and until the VM sees the packet, but only a relatively small part of this time was spent actually transitioning between the VM and the hypervisor. Instead, most time was spent in the networking layers of the host Linux OS for KVM, and in the Dom0 Linux OS for Xen. The same was true for the outgoing network path. The fundamental reason for Xen being slower than KVM in this case is due to Xen's I/O model, which uses a special VM, Dom0, to handle physical network packets. Xen must perform expensive scheduling operations of the application VM and Dom0 and expensive mapping and unmapping operations to set up shared data mappings between the application VM and Dom0.
These results are surprising given a typical focus on low-level hypervisor operations performance; instead, the hypervisor design and I/O model turns out to have a significant impact on real application performance.
ARM hypervisors do not necessarily benefit from a fast transition cost between the VM and the hypervisor, because hypervisor software requires more complex interactions than simply switching between execution contexts to support common macro operations like supporting I/O. Surprisingly, KVM ARM actually exceeds the performance of Xen ARM for most real application workloads involving I/O. This is due to differences in hypervisor software design and implementation that play a larger role than how the hardware supports low-level hypervisor operations.
The new improvements to the ARM architecture, the Virtualization Host Extensions (VHE) may allow Type 2 hypervisors to bring ARM's fast VM-to-hypervisor transition cost to real application workloads involving I/O given the combination of a simpler I/O model for Type 2 hypervisors and a VM-to-hypervisor transition cost that is potentially lower than on x86 systems.
The published papers describes more performance numbers and offer more detailed explanations as well as give an in-depth overview of VHE and how Type 2 hypervisors benefit from these architectural changes.
Christoffer Dall, Linaro Virtualization Tech Lead, will be presenting this work at ISCA 2016 in Seoul, Korea, this on Monday 20 at June 4-5pm in session 4B: NoC / Virtualization. http://isca2016.eecs.umich.edu.
(1): http://www.cs.columbia.edu/~cdall/pubs/isca2016-dall.pdf]]>
Linaro Ltd, the collaborative engineering organization developing open source software for the ARM® architecture, announced today that Thundersoft has joined the 96Boards initiative as a Steering Committee member and Manufacturing Partner. This new collaboration allows Thundersoft to both influence the development of the 96Boards specifications and initiative, and produce 96Boards products with support provided on the 96Boards forum.
96Boards is Linaro's initiative to build a single software and hardware community across low-cost development boards based on ARM technology. Thundersoft is a leading Smart Device Platform Technology Provider specialized in the mobile OS segment. Thundersoft will be able to leverage 96Boards to provide its services to a broader market with more rapidly developed and easily maintained solutions benefiting from the platform standardization provided by the initiative.
"Historically, there has been no affordable way for developers to work on the latest ARMv8 64-bit hardware," said Larry Geng, CEO of Thundersoft. "The 96Boards initiative has helped to provide the ARM ecosystem with a standardized, silicon-independent platform that is opening up new markets by delivering the latest ARM technology at a reasonable cost to a much wider audience. We expect that by helping develop the 96Boards initiative, we will encourage a broader range of engineering talent to develop on ARM, which will in turn lead to accelerated innovation and faster time to market for new products that will benefit from Thundersoft services."
The 96Boards steering committee now includes ten companies who are working together on Consumer, Enterprise, Digital Home, Networking and IoT specifications. To date, the Consumer and Enterprise Edition specifications have been released with Consumer edition boards readily available and the first Enterprise edition board currently in production and expected to ship in the next month. In total, there are now over twenty main boards being sold or under development with a large number of mezzanine products and other accessories being released.
"Thundersoft joining as a Steering Committee member and Manufacturer Partner is a big step forward in the maturing of the 96Boards initiative," said Yang Zhang, Director of 96Boards. "Thundersoft is well positioned to provide a software service to our existing members engaged in 96Boards and their customers who are developing next generation solutions based on the 96Boards specifications. We look forward to the initiative fostering increased cooperation opportunities for Thundersoft in both hardware and software development."
About Linaro
Linaro is leading collaboration on open source development in the ARM ecosystem. The company has over 200 engineers working on consolidating and optimizing open source software for the ARM architecture, including developer tools, the Linux kernel, ARM power management, and other software infrastructure. Linaro is distribution neutral: it wants to provide the best software foundations to everyone by working upstream, and to reduce non-differentiating and costly low level fragmentation. The effectiveness of the Linaro approach has been demonstrated by Linaro's growing membership, and by Linaro consistently being listed as one of the top five company contributors, worldwide, to Linux kernels since 3.10.
To ensure commercial quality software, Linaro's work includes comprehensive test and validation on member hardware platforms. The full scope of Linaro engineering work is open to all online. To find out more, please visit http://www.linaro.org and http://www.96Boards.org
About Thundersoft
Thundersoft, listed on the Shenzhen Stock Exchange (SZ: 300496), is the world's leading provider of mobile operating system and smart device solutions. Focusing in areas like mobile phone/tablet, IoT, automotive and enterprise, etc., with full-stack engineering resource covering mobile software, hardware and all layers of operating system, rich technology/solution portfolio, strategic partnership with key SoC/ISV/IHV vendors, and global support networks, Thundersoft is able to provide professional, solid, responsive and turn-key mobile platform technology, services and solutions, and enable customers worldwide to build high-quality and quick-to-market products. Learn more at www.thundersoft.com
The Linaro Digital Home Group (LHG) is pleased to announce a reference build of W3C EME Clear Key on the 96Boards HiKey platform. The build uses open source components to implement an HTML5 browser-based playback of encrypted content using OP-TEE running on ARM TrustZone. The OpenEmbedded build system is employed in this Linux-based implementation.
This Chromium browser-based implementation is an end-to-end solution that retrieves encrypted video from a server and locally provide secure decryption via OP-TEE.
The build instructions are provided here: https://github.com/kuscsik/96boards-manifest
A link to real encrypted video content to playback!
All 64-bit execution mode in both Secure (including Trusted Applications) and Non-secure environments.
The build uses a pre-built binary (fip.bin) for the ARM Trusted Firmware and OP-TEE build. Using a Firmware Image Package (FIP) allows for packing bootloader images (and potentially other payloads) into a single archive that can be loaded by the ARM Trusted Firmware from nonvolatile platform storage. A driver to load images from a FIP has been added to the storage layer and allows a package to be read from supported platform storage.
Link to player (part of the readme instructions): http://people.linaro.org/~zoltan.kuscsik/chrome/eme_player.html
For a more detailed description of the Linaro Clear Key solution, please see this document: https://wiki.linaro.org/LHG/LHGPublicDocuments?action=AttachFile&do=view&target=KeySystems.pdf
The W3C EME specification details the messaging flow between elements that support encrypted media recognition and support for obtaining keys to decrypt the video. The EME Clear Key solution is required for any compliant EME solution.
The content is decrypted using an AES Decryption Trusted Application that resides in Secure World running on the secure OP-TEE OS in ARM TrustZone.
Linaro ClearKey Implementation
So go ahead and give this a try. The engineers in LHG have also created full W3C EME OP-TEE integrations with commercial DRMs such as Microsoft's PlayReady and Google's Widevine on both Linux- and Android-based solutions. You will be able to see and hear more about LHG's work in this area in our upcoming Connect event in Las Vegas in September (LAS16).
W3C Encrypted Media Extensions
I arrived at the Vegas hotel along with Dale, from Form AV, on Thursday afternoon after a ten hour flight and 30-minute taxi drive – just in time for the heatwave. Sunny and 42 degrees Celsius (107 Fahrenheit), it was quite the contrast to the rainy, grey London we flew out from. Luckily the average temperature for September in Las Vegas is 35 degrees celsius (95 degrees Fahrenheit) which will still be warm but nice enough to enjoy the outdoor amenities.
We were met by our Event Manager, Bobbi, who got us checked into our fantastic suites. The suite was beautifully decorated and felt very homely, with a spacious bathroom, big comfy bed and great view of the mountains surrounding Vegas.
In the evening we had dinner at a Mexican restaurant called Cantina Laredo in Tivoli Village, an area full of restaurants and shops about a 15 min walk away from the Marriott. We went back to Tivoli Village on our last evening in Vegas for steaks at Echo & Rig. Both times, the food was superb and the atmosphere great. In Tivoli Village there are many more restaurants worth checking out – you can find Italian food (Brio Tuscan Grille), Japanese food (Kabuki Japanese restaurant) or cupcakes (Cupcakes by Kate) and waffles (Waffle Bar) for those with a sweet tooth.
Friday was a busy day that mainly involved walking around the conference centre and planning the event. What makes the centre so nice is that there is a lot of outdoor space – it is very green with water everywhere. It really does feel like an oasis in the desert and will no doubt allow for the occasional respite from the busy Linaro Connect schedule.
One of the highlights of the trip was when we got to do a menu tasting. The chef prepared two salads, five main courses and two desserts. Needless to say we struggled to finish it all but we made a valiant attempt! My personal favorites were the Creole chicken and the baked vegetable baguette but everything was delicious.
Saturday we decided to brave the strip. The Marriott arranged for a car to pick us up and drive us 20 minutes to the Border Grill at Mandalay Bay – a Mexican restaurant which I would highly recommend for a meal out in town. The initial plan was to then wander round the strip but that was before we ventured outside… being Scandinavian I am very rarely exposed to this kind of heat so we quickly and sensibly scrapped the idea of walking along the strip. Instead, we ordered Uber and Lyft to drive us around which turned out to be a very efficient and low cost way of getting around Vegas!
Sunday the Marriott treated us to 50 minute Swedish massages at the Spa Aquae. I am not normally a fan of massages, I tend to try so hard to relax that I end up overthinking it and becoming tense. I nearly decided to opt out of this one but I'm glad I didn't. It was AMAZING. For someone who has never really enjoyed massages, I was blown away by how relaxed I felt afterwards. After the massage, I spent a good few hours in the spa, which is beautifully done up with hot tubs, an outdoor pool and saunas. Last but not least, I went for a quick swim in the outdoor pool before we had to head to the airport. Make sure you visit the spa and the swimming pool at least once during your stay at the JW Marriott!
Linaro Connect Las Vega 2016 will be held September 26-30, 2016. More information on this event can be found at: http://connect.linaro.org/las16/


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Index of content:
Volume 59, Issue 3, March 1991
- Letters to the Editor
Response to ''Women—Why so few?'' by Michael Levin [Am. J. Phys. 5 8, 905–906 (1990)]59(1991); http://dx.doi.org/10.1119/1.16560View Description Hide Description
Recent history of tower and mine searches for non‐Newtonian gravity59(1991); http://dx.doi.org/10.1119/1.16561View Description Hide Description
- Top
- Editorial
Editorial: Memorable papers from the American Journal of Physics, 1933–199059(1991); http://dx.doi.org/10.1119/1.16562View Description Hide Description
- Top
- Papers
Relativistic solutions to the falling body in a uniform gravitation field59(1991); http://dx.doi.org/10.1119/1.16563View Description Hide Description
Many different solutions to the problem of the relativistic particle in a uniform gravitational field have been offered. The fact that different, apparently correct, solutions to the same problem exist is in itself a puzzle. A resolution to this puzzle is found by exploiting the equivalence principle to reduce the problem to the observations made by an accelerated observer of objects moving inertially in a background inertial frame. It is shown that some solutions, those arising from a truly curved space‐time, cannot be treated in this manner. It is found that differences in the remaining solutions arise because the authors use coordinate displacement to describe the motion rather than proper distance. The coordinate systems of these different accelerated frames are distorted and produce different apparent motions of objects in the background frame. When the ''right'' variables are used all motions are identical.
The physics of the drive in golf59(1991); http://dx.doi.org/10.1119/1.16564View Description Hide Description
With the personal computer the undergraduatephysics student can investigate interesting physical systems. This is illustrated with a study of golf drives predicted from experimentally measuredlift and drag coefficients which give forces nearly proportional to the square of the velocity of the ball. Their interplay gives a surprising linear dependence of range on initial velocity, in good agreement with empirical formulas but in contrast with the quadratic dependence discussed in introductory physics courses. Spin damping is easily introduced and found to decrease the range for a given launch angle. The exploration of quantitative and qualitative differences between the trajectories produced by measured drag and lift forces and those predicted by a model with a linear velocity dependence illustrates the scientific method at work.
A simple derivation of the Doppler effect for sound59(1991); http://dx.doi.org/10.1119/1.16565View Description Hide Description
The Doppler formulas for sound waves are derived in a particularly simple way from a space‐time diagram. The method used emphasizes use of space‐time diagrams in a quantitative way.
Chaoticlike motion of a l i n e a r dynamical system59(1991); http://dx.doi.org/10.1119/1.16566View Description Hide Description
The free oscillations of a chain of identical masses connected by identical springs can be very complicated, resembling the chaotic oscillations of nonlinear systems. These oscillations, however, differ in significant ways from chaotic oscillations. They are actually oscillations of a type called almost periodic that are also observed in nonlinear systems. This article solves the equations of motion for longitudinal oscillations in a finite linear chain. The resulting oscillations are discussed and compared with chaotic oscillations. The linear chain can easily be set up as a demonstration.
Exact partial wave analysis for scattering by a segmented potential59(1991); http://dx.doi.org/10.1119/1.16567View Description Hide Description
By approximating the scattering potential in the lth partial wave equation with a series of constant segments, an exact solution in terms of spherical Bessel and Neumann functions becomes available. Continuity at the segment boundaries is achieved with the aid of a simple 2×2 matrix formalism and leads to exact expressions for the scattering phase shifts.
The Runge–Lenz vector for the two‐dimensional hydrogen atom59(1991); http://dx.doi.org/10.1119/1.16568View Description Hide Description
The recent discovery of novel properties possessed by two‐dimensional systems has led to the investigation of properties of the hydrogen atom in two dimensions. With proper definition of the system, the so‐called Runge–Lenz vector may be defined for this system, and shown to be related to the underlying O(3) symmetry, just as for the three‐dimensional system, although some interesting aspects are revealed.
Equivalent magnetization approach for calculating magnetic fields of localized steady‐state current distributions59(1991); http://dx.doi.org/10.1119/1.16569View Description Hide Description
In the evaluation of the magnetic fields produced by magnetized bodies in a vacuum the bodies can be replaced by fictitious ''magnetization'' currents. Therefore, it should be possible to calculate magnetic fields of real currents by replacing them with fictitious magnetized bodies. This possibility is explored in the present article. In one of the examples considered the net magnetic field due to a uniformly charged sphere spinning on its axis is calculated. Other applications are suggested.
The use of a nearly confocal interferometer for the study of transverse modes of a cavity59(1991); http://dx.doi.org/10.1119/1.16828View Description Hide Description
An experiment has been developed that enables students to use a nearly confocal interferometer to measure and verify the predicted frequency spacing of adjacent transverse modes of the nearly confocal interferometer.
Springs and masses as a stationary wave problem59(1991); http://dx.doi.org/10.1119/1.16570View Description Hide Description
The two‐degree‐of‐freedom oscillator consisting of two masses and three springs whose masses are not negligible is studied in terms of stationary waves. The corrected eigenfrequencies are calculated. It is shown that a recently published treatment of the same problem is valid only if the masses of the springs are very much smaller than the masses of the oscillating bodies.
Learning optics with optical design software59(1991); http://dx.doi.org/10.1119/1.16833View Description Hide Description
The use of commercially available optical design software is described as a tool to aid in learning geometrical optics. Common optical phenomena are easily modeled and displayed graphically. The interactive nature of this type of software allows the student to develop a deeper understanding of the laws of optics.
Electromagnetic wave propagation in media with complex refractive indices and transmission through absorbing films59(1991); http://dx.doi.org/10.1119/1.16571View Description Hide Description
The usual textbook treatment of electromagnetic (em) wave propagation across the boundary separating two dielectrics is generalized to materials characterized by complex refractive indices. Such materials are being investigated intensively and possess interesting and potentially useful properties in the infrared (IR) and optical bands. The sum of the transmission and reflection coefficients at the boundary in these materials does not add to unity, as in the case of perfect dielectrics, and the reason for this unexpected behavior is examined. Since these materials are usually fabricated in film form, appropriate transmission and reflection coefficients of thin and thick films with arbitrary refractive indices are derived (taking account of multiple reflections) to point out the differences introduced by the complex nature of the refractive index which have not been included in previous results or which have generally not been emphasized. Results are also presented for films deposited on thick substrates of arbitrary refractive indices since this is the common mode of fabrication. Graphs are presented to illustrate the transmission behavior of a thin absorbing film with and without a substrate.
Perturbative treatment of a general driven time‐dependent oscillator in a time‐dependent basis59(1991); http://dx.doi.org/10.1119/1.16572View Description Hide Description
This paper examines the possibility of applying the time‐dependent perturbation theory to the systems with a time‐dependent unperturbed part. Analyses indicate that time‐dependent perturbation theory is valid even if the unperturbed Hamiltonian H 0 depends on time, provided that the pseudostationary states of H 0 are known. It is also shown that this new perturbative treatment provides a useful tool for tackling the problem of a general driven time‐dependent oscillator.
Concept of relativistic temperature via the Crawford technique59(1991); http://dx.doi.org/10.1119/1.16573View Description Hide Description
Using the Crawford technique of calculating the energy loss of gas atoms colliding with a wall, it is demonstrated that relativistic temperaturemeasures the average value of the product of the atomic velocity with momentum, i.e., 〈v p〉 per translational degree of freedom. This confirms a passing observation made by ter Haar and Wergeland 20 years ago. The mean number of collisions needed to attain equilibrium can also be estimated theoretically.
A magnetic model for the demonstration of phase transitions and excitations in molecular crystals59(1991); http://dx.doi.org/10.1119/1.16574View Description Hide Description
A magnetic model for the demonstration of structuralproperties and the lattice dynamics of molecular crystals is presented. It is used to visualize an orientational order–disorder phase transition. The orientational order of the low‐temperature phase observed on the model is also obtained from a mean field calculation. A simple theory for harmonic excitations of the model is presented, which gives the dispersion relation for an infinite crystal. The frequencies of the observed resonances of the finite model are compared with the results of a numerical eigensystem analysis and with the dispersion relation. Within the limitations given by the construction of the model the results are in rather good agreement.
New quantum mechanical perturbation technique using an ''electronic scratchpad'' on an inexpensive computer59(1991); http://dx.doi.org/10.1119/1.16575View Description Hide Description
The authors have developed a new method for doing numerical quantum mechanical perturbation theory. It has the flavor of Rayleigh–Schrödinger perturbation theory (division of the Hamiltonian into an unperturbed Hamiltonian and a perturbing term, use of the basis formed by the eigenfunctions of the unperturbed Hamiltonian) while turning out to be a variational technique. Furthermore, it is easily implemented by means of the widely used ''electronic scratchpad,'' MathCAD 2.0, using an inexpensive computer. As an example of the method, the problem of a harmonic oscillator with a quartic perturbing term is examined.
Cumulant expansions in statistical and quantum physics59(1991); http://dx.doi.org/10.1119/1.16576View Description Hide Description
Two examples are given of the use of cumulant expansions for systems of particles with hard‐core two‐body interactions. One of these, in classical statistical mechanics, is shown to lead to virial coefficients. An analogous procedure in quantum mechanics produces energy level shifts due to hard‐core interactions that are expressed in terms of the t matrix.
- Top


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Swindon Vs Rovers Moved And Now On Sky
What's being said in the forum now?Click to join the Vital Bristol Rovers forum!
Bristol Rovers game against swindon Town has been moved due to the game being picked to be shown on Sky Sports.
The game was due to be played on Saturday 9th October at The County Ground, but has now been moved to Monday 11th October with a 7-45pm kick off and will be shown on Skys Monday Night Football show.


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Both passenger and driver's side electric windows are total erratic. Must pull or push to raise or lower to get them started. Passenger side sometimes works perfect but then will quick for weeks. What's up. I replaced the control system. It sounds as if the window is rubbing which I don't think it is. What do I do? Thanks.
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Welcome to our recipe page! These recipes offer easy, nutritious, seasonal, and economically priced meal ideas. Check back often as we add new recipes every week.
Budget Recipes
From "Feed Four for a Week on $125"
A Sampling of Our Recipes
Garden Fresh Asparagus Soup
Asparagus Quinoa Salad
Asparagus Wild Rice Chicken Salad
Lentil Rhubarb Soup
Asparagus with Goat Cheese and Lemon
Asparagus Pea Saute
Rhubarb Bars
Strawberry Clafouti
Strawberries with Chocolate Cinnamon Dipping Sauce
Featured Recipe
Creamy Vegan Strawberry Smoothie
2 cups fresh or frozen strawberries
1 1/2 cups coconut water or milk
1/2 cup raw cashews
1/4 cup chopped pitted dates (about 3-4 dates - less if you don't want it as sweet)
1 teaspoon vanilla
pinch sea salt
- Place the coconut water, cashews and dates in your high speed blender and puree on high until smooth and creamy.
- Add the vanilla extract, salt and strawberries. Blend on high until rich and creamy.
From healthyblenderrecipes.com
Asian Turkey Burgers
Flavor your turkey burgers Asian-style for a taste treat!
Asian Turkey Lettuce Wraps
A flavorful, Asian-inspired turkey filling for stuffing inside fresh lettuce leaves.


text: 000 FXUS64 KTSA 241545 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 1045 AM CDT SUN JUL 24 2016 .DISCUSSION... Current forecast in good shape heading into the afternoon. A little more sky cover to contend with than at this time yesterday...but dont think it will hamper temperatures. Thunderstorm coverage this afternoon should be a little further west than yesterday as the upper ridge loses its hold just a little bit. Current pops for the afternoon look good as well...along with remaining first period elements. No update planned at this time. Will refresh the NPW before 1600z. && .TSA Watches/Warnings/Advisories... OK...Heat Advisory until 9 PM CDT this evening for OKZ049-053>076. AR...Heat Advisory until 9 PM CDT this evening for ARZ001-002-010-011- 019-020-029. && $$ SHORT TERM...23 LONG TERM....18


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Star Tracks
Gyllenhaal brings daughter Gloria to visit Uncle Jake in N.Y.C. Plus: Katy Perry, Michael Phelps, Sofia Vergara and more
Credit: Janet Mayer/Splash News Online
Published: Wednesday Aug 01, 2012 | 05:00 PM EDT
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